The present invention generally relates to allocating network resources. More specifically, the present invention relates to reserving and committing network resources based on an authorized quality of service.
The known signaling architecture H.323 is an International Telecommunications Union (ITU) defined standard that describes how multimedia communications occur between terminals, network equipment and services on local area networks (LANs) and wide area networks (WANs) that do not provide a guaranteed quality of service (such as Internet Protocol (IP) networks). Quality of service is a measure of communication service quality during a call, and can include, for example, the bandwidth, delay and latency associated with the call. In networks using connectionless xe2x80x9cbest effortxe2x80x9d delivery models, the quality of service typically is not guaranteed; the H.323 is a signaling architecture for such a network.
The H.323 provides a range of implementation options including gatekeeper-routed signaling. In the H.323 standard, gatekeepers map LAN address aliases to IP addresses and provide address lookups when needed. Gatekeepers also exercise call-control functions to limit the number of H.323 connections and the total bandwidth used by these connections in an H.323 xe2x80x9czone.xe2x80x9d Although the gatekeeper is not necessary within the H.323 standard, when a gatekeeper is present in a network, network terminals must make use of its services. In other words, gatekeepers maintain state information for each individual call and all call signaling must pass through the gatekeepers.
The gatekeeper implementation of the H.323 standard, however, suffers several shortcomings. First, the equipment associated with gatekeepers needs to be extremely reliable so that the gatekeeper is available throughout the course of the call. If the gatekeeper-related equipment fails during a call, the call fails because the state information for the call maintained solely at the gatekeeper is lost. Second, the gatekeeper-related equipment likely cannot scale in a cost effective manner because maintaining the state information and performing the messaging associated with H.323 is complex and processor intensive. Finally, theft of service is possible by bypassing the gatekeepers to place unauthorized and unmonitored calls.
State information for a call between a calling party and a called party is established without maintaining the state information at a gate controller. A setup request for the call is received at an originating gate controller. The originating gate controller is connected to a trusted network. The calling party is associated with an originating interface unit coupled to an untrusted network. The setup request for the call is authorized. The authorized setup request is sent to the called party. State information for the call is formatted based on a setup acknowledgment message received from the calling party. The state information for the call is sent from the originating gate controller to the originating interface unit without maintaining the state information at the originating gate controller.